Herpes simplex virus, especially types one and two (HSV-1 and HSV-2), is one of the most feared diseases in the world today. No known cure is available for the treatment of this disease. Commercial drugs provide only temporary relief. Based on anecdotal evidence and preliminary tissue culture studies, certain platinum complexes show considerable promise as effective therapeutic agents for herpetic infections. The research proposed in Phase I will be concerned with testing ten platinum complexes in a combination of in vitro and in vivo studies. One of these, cisplatin, will be investigated extensively in order to bring it to the stage of clinical testing by the end of Phase I. Six other platinum complexes, all known antitumor compounds, will be investigated in vitro against various strains of HSV-1 and HSV-2. The remaining three complexes, newly synthesized in this laboratory and containing the cis-[Pt(NH3)2]2+ moiety bound to three known antiviral drugs (acyclovir, ara-ADA, and cyclaradine), will be characterized and in vitro testing will be initiated. Phase II will involve a) extensive clinical evaluation of cisplatin with the aim of commercial application, b) completion of the in vitro and in vivo studies of the remaining nine complexes, and c) the onset of clinical trials for the most promising antivirals in this group.